Style Summary:

We are making a coconut IPA based on our American IPA.

More details can be found here: BJCP Style Details

A small excerpt from the source about this style:
“Overall Impression: A decidedly hoppy and bitter, moderately strong American pale ale, showcasing modern American or New World hop varieties. The balance is hop-forward, with a clean fermentation profile, dryish finish, and clean, supporting malt allowing a creative range of hop character to shine through.” - BJCP -

…of course, with some coconut ;)

Coconut Additions

Here is one of the first things The Hop and Grain note: Coconut tends to accompany darker, sweeter beer styles, such as stouts and porters, much better than lighter styles. I agree. However we have an idea for a tropical ipa with coconut. We will aim to be on the lighter side, but want solid coconut flavor. Homebrewtalk had a suggestion I like where the brewer utilized a 1lb coconut and toasted it before adding to the fermentation carboy. That’s what I decided to do. I bought a coconut and used a chisel to cut a square hole into the coconut. After draning the coconut I sawed it in half and scraped the flesh out. Finally I toasted at 350 degreed F for about 15-20 minutes. While it was toasting I boiled the coconut water down to shrink it’s volume and saved for later. Finally I poured vodka over the coconut in a jar till it was submerged. I added the water which had shrunk to about a cup of fluid. It will sit for approximately 5 days before we add to the fermenter.

Below are some pics of my process:

The Coconut

It was already sort of shaved down and without hair

It was already sort of shaved down and without hair

Coconut Chopped

I didn’t use the grater. The spoon and knife were enough. Notice how much coconut water is in the jar!

I didn’t use the grater. The spoon and knife were enough. Notice how much coconut water is in the jar!

Coconut Toasted and soaked in it’s own water and vodka

After reducing coconut water, filled jar with approx 3/4 cups vodka and reduced water.

After reducing coconut water, filled jar with approx 3/4 cups vodka and reduced water.

Kitchen Constants:

* Small Note: we will use math mainly from “Designing Great Beers” by Ray Daniels as it is intuitive and easy to follow for the modern day home brewer.

Recipe Style Date OG FG
Coconut IPA Coconut IPA 10_28_2018 1.063 1.011

Fermentables

Link to Potential Gravity From Grain Values

Grains Lbs Potential_SG EZ_Water_Code SRM Percent
Pale Malt (2 Row) US 12.31 1.036 2 2 1

Theoretical OG from this is: 1.0651445

Hops

So in the hop profile I want to avoid the resinous part of the hops addition or contribution to flavor. I think it is harsh. In general I want citrusy and fruity hops, but we will boil them to get the bitterness to come through.

IBU is supposed to be in the range of 40-70. Here are some beers to model ours after:
* Sierra Nevada Pale Ale: 38 IBU
* Heady Topper: 75 IBU
* Dogfish Head 90 min IPA: 90 IBU

Citra boasts 60-70% of its hop oil volume in mercene which is known for its highly flavorful citrus and fruit flavors and or aromas. We will dry hop post fermentation so the yeast do not interfere with its flavor. Mosaic is also pretty flavorful (48-55% Mercene) and we will use it to bitter the beer. I believe that the isomerization of the hop oils when you boil leaves you with only bitterness flavor. Instead I intend to boil the hops for only 30 minutes. The achieve the correct IBU level, I will just use more hops. I believe that by not being conservative with the hop amount, I will achieve plenty of bitterness, while keeps the integrity of the hop flavors. After reading a bit about boiling hops, I’ve come the the conclusion that most flavor and or aroma is lost after boiling and it would never really matter what hop you used for boiling. Since I’m not trying to make the hoppiest beer in the world and flavor matters, keeping the characteristics of these hops intact is paramount.

Hop Hop_Type Alpha_Acid_Percent Weight_Oz Boil_Time Utilization IBU
Galaxy pellet 0.141 1.2 30 0.24 56.541215
Australian Vic Secret pellet 0.210 0.5 5 0.06 8.771908
Australian Vic Secret pellet 0.210 1.5 0 0.00 0.000000

Predicted ABV: 65.3131229

Mash

  • Mash_Thickness: 1.25
  • Sacc_Rest_Temp: 149
  • Mash_Duration: 60
  • Init_Grain_Temp: 70
  • Infusion_Temp: 161.64
  • Mash_Volume_Gal: 3.846875
  • Sparge_Vol: rSVPMO
  • Mash_Out_Vol: 2.0186935

Water Chemistry

Formulas and constants from here
Bostons Water Supply Chemistry link

Boston Water Supply (ppm or mg/L):

  • Init_Ca: 4
  • Init_Mg: 1
  • Init_Na: 32
  • Init_Cl: 23
  • Init_SO4: 6
  • Init_HCO3_CaCO3: 40

Adjustments: (ppm or mg/L)

  • pH_DOWN_Gypsum_CaSO4: 10
  • pH_DOWN_Cal_Chl_CaCl2: 5
  • pH_DOWN_Epsom_Salt_MgSO4: 5
  • pH_UP_Slaked_Lime_CaOH2: 0
  • pH_UP_Baking_Soda_NaHCO3: 0
  • pH_UP_Chalk_CaCO3: 0

Summary:

  • Estimated Room Temp Mash pH: 5.5426586
  • Desired Room Temp Mash pH: 5.4 - 5.6
  • Effective Alkalinity: 32.7868852
  • Residual Alkalinity: -167.719023

Yeast

  • Yeast_Strain: SafAle US-05
  • Attenuation: 72
  • Initial_Cell_Count_Billions: 308.2150103
  • Pitched_Cells_Billions: 308.2150103
  • Liters_For_Starter: 0
  • Time_For_Starter: 0

ABV (predicted): 6.1224076

Fermentation

We need to keep the hop character in the beer. This means we need to ferment somewhat cold for an ale or rather on the cold side of the yeast fermentation temperature range. Safale US-05 says 59 - 71.6 degrees fahrenheit. We will shoot for 59. As for any variation. The first week will be tightly controlled. Then we we will put a Kolsch in the fridge and the temp of the beer will probably average out to 70 degrees F for the remaining 3 weeks.

Temp Days
59 7
70 7
70 7
70 7